I've searched this forum but couldn't find a reference to this, so here goes.

When item A has a requirement, say 78 strength, and the character has, say, 75 strength, but equips item B that gives it +4 strength, giving it 79 total, item A can now be equipped.

However, if after item A is being equipped, item B is removed, item A is still equipped, despite the character now not meeting the requirements (and is painted red on the items equipped screen).

Usually removing item B should've also removed item A, but that is not the case. This is not a show-stopper, and if anything is benefiting the player, who can still use item A, despite not meeting the requirements, but still it is a bug, IMO